Method of welding a friction material to a reinforcing member

Abstract

A method of making a brake friction pad which includes the steps of placing a sintered friction material into a retainer cup, heating the friction material and the retainer cup to a predetermined temperature in an inert atmosphere, and striking the friction material with a single blow of a predetermined force. This single blow increases the density of the friction material and establishes a metallurgical bond between the friction material and the retainer cup.

We claim: 
     
       1. A method of attaching a sintered friction material to a retainer comprising the steps of: placing the sintered friction material on said retainer;   heating said sintered friction material and said retainer to a uniform temperature between 1400° to 1650° F; and   striking said heated sintered friction material and said retainer with a single compressive force between 7000 and 20,000 psi to compact said friction material to a predetermined density and to bond said sintered friction material to said retainer.   
     
     
       2. The method, as recited in claim 1, further including the step of: locating said sintered friction material and said retainer in an inert atmosphere during said uniform heating.   
     
     
       3. The method, as recited in claim 2, further including the step of: transferring said heated sintered material and retainer from said inert environment to a hydraulic press when said predetermined temperature is reached.   
     
     
       4. A method of manufacturing a brake pad comprising the steps of: filling a mold with a copper base friction material;   densifying the copper base friction material in said mold;   placing the densified copper base friction material in a furnace;   raising the temperature in the furnace to sinter said copper base friction material;   removing the sintered copper base friction material from said furnace;   placing the sintered copper base friction material sn a retainer;   heating said sintered copper base friction material and retainer until a uniform temperature between 1400° to 1900° F is reached; and   striking said heated retainer and sintered copper base friction material with a single compressive force to compact said copper base friction material to a predetermined density and to metallurgically bond said copper base friction material to said retainer.   
     
     
       5. The method, as recited in claim 4, further including the step of: filling said furnace with an inert atmosphere during the sintering of said copper base friction material.   
     
     
       6. The method, as recited in claim 5, further including the step of: grinding said copper base friction material to establish a desired thickness.